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CN-122022167-A - Urban river water sensitive landscape reconstruction demand identification method based on GIS

CN122022167ACN 122022167 ACN122022167 ACN 122022167ACN-122022167-A

Abstract

The invention relates to a GIS-based urban river water-sensitive landscape modification demand identification method. The method comprises the steps of firstly obtaining and preprocessing urban river channel vectors, digital elevation models and earth surface coverage data, linearly segmenting the river channel vector data into river segment analysis units, and constructing corresponding shore zone analysis units by taking a river channel center line or a shore line as a reference to expand distance to the land side. And extracting multidimensional space characteristic factors in each shore zone unit, associating the multidimensional space characteristic factors with corresponding river reach units, carrying out direction unification and standardization treatment on factor values, and calculating water-sensitive landscape reconstruction requirement indexes of each river reach according to the factor values. And finally grading all the river reach units according to the indexes, and outputting the spatial distribution results and the transformation demand grades. Compared with the prior art, the method has the advantages of solving the difficult problem of data acquisition, strong feasibility of planning stage and the like.

Inventors

  • QIU JIANG
  • WANG JIANBIN

Assignees

  • 上海应用技术大学

Dates

Publication Date
20260512
Application Date
20260130

Claims (10)

  1. 1. A GIS-based urban river water sensitive landscape modification demand identification method is characterized by comprising the following steps: s1, urban river vector data, digital elevation model data and earth surface coverage data of an area to be analyzed are obtained and preprocessed; s2, carrying out linear piecewise processing on the preprocessed urban river vector data to obtain a plurality of river reach analysis units, and aiming at each river reach analysis unit, expanding a preset distance to the land side by taking a river center line or a shoreline as a reference to construct a corresponding shoreside analysis unit; S3, extracting a space characteristic factor set containing a plurality of space characteristic factors from each shore zone analysis unit based on the preprocessed digital elevation model data and the ground surface coverage data, and associating the numerical value of each extracted space characteristic factor to a corresponding river reach analysis unit; s4, carrying out direction unification and standardization on the numerical values of the space characteristic factors in the space characteristic factor set, and calculating to obtain the water-sensitive landscape reconstruction requirement index values corresponding to the river reach analysis units based on the standardized space characteristic factor set; And S5, grading all the river reach analysis units according to the demand index value to obtain and output the spatial distribution result of each river reach analysis unit and the water-sensitive landscape modification demand level.
  2. 2. The GIS-based urban river water-sensitive landscape modification demand identification method according to claim 1, wherein the preprocessing in S1 comprises coordinate system unification, spatial registration and resolution unification.
  3. 3. The urban river water-sensitive landscape modification demand identification method based on the GIS is characterized in that in the S2, the specific mode of segmentation processing comprises equidistant segmentation of a river center line according to a preset length, or identification of preset nodes and segmentation of a river by taking the preset nodes as boundaries, wherein the preset nodes comprise bridges, gate stations, branch sink inlets or shoreline form mutation points on the river.
  4. 4. The urban river water-sensitive landscape modification demand identification method based on GIS (geographic information system) of claim 1, wherein the construction mode of the shore zone analysis unit in S2 comprises the steps of setting a fixed preset distance, generating a buffer zone with a fixed width based on the fixed preset distance, or determining a grading preset distance according to river grade, peripheral land type or boundary conditions along the river, and generating the buffer zone with a preset grading width based on the grading preset distance; After the buffer area is generated, the buffer area is cut by utilizing the water body image layer, so that the water area is removed, and a final shore zone analysis unit is obtained.
  5. 5. The urban river water-sensitive landscape modification demand identification method based on GIS of claim 1, wherein the spatial characteristic factors in S3 comprise a shore zone hardening degree factor extracted based on earth surface coverage data, an ecological or landscape spatial condition factor extracted based on earth surface coverage data, and a rainfall and flood pressure factor or a confluence potential factor obtained based on digital elevation model data analysis.
  6. 6. The GIS-based urban river water-sensitive landscape modification demand identification method of claim 5, wherein the shore hardness factor comprises at least one of a shore impervious surface proportion, a building and road coverage proportion and a hard shoreline proportion; The ecological or landscape space condition factors comprise at least one of a land green land proportion, a vegetation coverage or vegetation index, a green land patch connectivity index and an open space proportion.
  7. 7. The GIS-based urban river water-sensitive landscape modification demand identification method is characterized in that the rainfall flood pressure factor or the confluence potential factor is obtained by performing hydrologic terrain analysis on digital elevation model data, and the hydrologic terrain analysis comprises at least one of depression filling calculation, flow direction calculation, confluence accumulation calculation and gradient calculation.
  8. 8. The urban river water-sensitive landscape modification demand identification method based on GIS (geographic information System) as claimed in claim 5, wherein the spatial characteristic factors further comprise social-sensitive exposure factors, and the social-sensitive exposure factors are extracted by counting the number, density or weighted density of POIs (Point of interest) in a shore zone analysis unit or in a preset range adjacent to the shore zone analysis unit, wherein the POIs comprise schools, hospitals, living areas and pension facilities.
  9. 9. The urban river water-sensitive landscape modification demand identification method based on the GIS according to claim 1, wherein the specific process of the S4 comprises the following steps: carrying out direction unification and standardization on the numerical value of each space feature factor in the space feature factor set, and outputting a standardization value of each space feature factor; And carrying out weighted summation on the standardized values of the space feature factors, or carrying out synthesis on the standardized values of the space feature factors through a multi-index fusion model, wherein the weighted summation or the synthesis result is the calculated water-sensitive landscape reconstruction requirement index value corresponding to each river reach analysis unit.
  10. 10. The method for identifying urban river water-sensitive landscape modification requirements based on GIS according to claim 1, wherein in the step S4, the direction unification processing specifically comprises: If a certain space characteristic factor value is increased to indicate that the transformation requirement is increased, setting the factor as a forward factor; Otherwise, if the space characteristic factor value is increased, the characterization condition is improved or the improvement requirement is reduced, setting the factor as a reverse factor, and carrying out reverse processing on the reverse factor to convert the reverse factor into a forward index; the normalization process employs at least one of a range normalization, a Z-score normalization, or a quantile normalization.

Description

Urban river water sensitive landscape reconstruction demand identification method based on GIS Technical Field The invention relates to the technical field of urban landscape modification, in particular to a GIS-based urban river water-sensitive landscape modification demand identification method. Background The urban river is an important carrier for urban rainfall flood converging and water ecological network, and the shore zone space simultaneously bears multiple functions of drainage safety, water environment improvement, ecological habitation, public activities and the like. With the increase of urban construction strength, problems of high hardening proportion of the bank zone, large water-impermeable surface ratio, rapid inflow of rainfall flood runoffs, insufficient ecological buffer zone, green space crushing, weaker accessibility and continuity of public space and the like occur in a plurality of urban river channels, so that the runoff peak value in the rainy season is increased, the overflow risk is increased, the self-cleaning capacity of the water body and the ecological service function are reduced, and the river channel landscape quality improvement and the water environment treatment effect are further restricted. The water-sensitive Urban Design (WATER SENSITIVE Urban Design, WSUD) emphasizes that Urban rainfall flood management and water environment system toughness are improved through landscaping measures such as greenbelts, wetlands, biological retention, permeation and accumulation in a mode of combining source emission reduction, process regulation and end purification, and ecological and landscape values are considered. Therefore, in the updating of urban river landscapes, how to identify the river segments which need to develop water-sensitive landscaping, clearly identify the space difference of the transformation demands and form a priority result which can be used for decision making is an important premise for advancing WSUD concepts to land. In the prior art, one type of method focuses on river channel flood control and drainage or water quality treatment engineering design, generally relies on field investigation, monitoring data or engineering parameters, and is difficult to realize rapid screening in a planning stage, the other type of method adopts a geographic information system (Geographic Information System, GIS) to carry out space analysis on flood risks, water system communication or land utilization and the like, but a multi-aspect river basin scale or urban area risk assessment is carried out, an output result often stays at a risk distribution or general planning suggestion level, a special identification process and an index system facing to 'water sensitive landscape transformation requirements' are lacked, and particularly, a repeatable requirement grading method which takes river channel segmentation and a shore zone unit as objects and can be carried out under the condition of open space data is lacked. Further, the existing method often has the problems of non-uniform index caliber, strong subjectivity of threshold and weight, difficulty in forming standardized output results and the like in the aspect of multi-source space factor fusion, and results have insufficient comparability and popularization. In the prior art, for example, in the invention patent with publication number CN117875564A, an earth surface radial flow source sink analysis method facing to urban three-dimensional landscapes is disclosed. According to the method, three-dimensional indexes of vegetation and buildings are extracted by acquiring point cloud data, meteorological hydrologic data and geospatial data, rainfall runoff simulation analysis is carried out by utilizing a hydrologic model, and therefore surface runoff depth and source sink turning points are obtained. However, the method has the following significant disadvantages when being practically applied to river landscape reconstruction planning: The data acquisition threshold is high and depends on a complex model, and the method core depends on the high-cost point cloud data and detailed meteorological hydrologic data to drive the hydrologic model. In the early screening stage of urban river planning, high-precision point cloud data is often lacking, and a hydrologic model is constructed and calibrated in a time-consuming and labor-consuming manner, so that quick and low-cost evaluation is difficult to realize. The method focuses on physical processes and neglects comprehensive transformation requirements, and mainly solves the problem of runoff simulation by focusing on analyzing physical hydrologic mechanisms such as surface runoff response, source sink turning points and the like. The method cannot comprehensively consider the hardening degree, social sensitivity and the existing landscape utilization conditions of the shore zone, so that the result can only reflect the water flow condition, but the urgency and feasibility o